Write head with reduced side to trailing shield spacing

ABSTRACT

A write head including a bearing surface and a write pole having a front surface that forms a portion of the bearing surface. The front surface has a leading edge, a trailing edge and side edges connecting the leading and trailing edges. The write head also includes side shields proximate to the side edges of the write pole, and a trailing shield over the write pole and the side shields. A trailing shield-write pole gap is present between the trailing edge and the trailing shield, and a trailing shield-side shield gap is present between the trailing shield and the side shields. The trailing shield-shield shield gap is substantially less than the trailing shield-write pole gap.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. patent applicationSer. No. 15/662,682, filed on Jul. 28, 2017, now U.S. Pat. No.10,141,014, the content of which is hereby incorporated by reference inits entirety.

BACKGROUND

Data storage devices use magnetic recording heads to read and/or writedata on magnetic storage media, such as data storage discs. Magneticrecording heads typically include inductive write elements to recorddata on the storage media. An inductive write element or transducer mayinclude a main pole having a pole tip and one or more return poles.Current is supplied to write coils to induce a flux path in the mainpole to record data on one or more magnetic storage layers of the media.

With ever-increasing levels of recording density in disc drives, thewrite element needs to have correspondingly better data-recordingcapabilities and needs to be reliable.

SUMMARY

Embodiments of the disclosure relate to a write head with a reduced sideto trailing shield spacing compared to a spacing between a write poleand the trailing shield to reduce erasure.

In one embodiment, a write head is provided. The write head includes abearing surface and a write pole having a front surface that forms aportion of the bearing surface. The front surface of the write pole hasa leading edge and a trailing edge. The write pole further includes sideedges connecting the leading edge to the trailing edge at the bearingsurface. The write head also includes side shields proximate to the sideedges of the write pole, and a trailing shield over the write pole andthe side shields. A trailing shield-write pole gap is present betweenthe trailing edge of the write pole and the trailing shield, and atrailing shield-side shield gap is present between the trailing shieldand the side shields. The trailing shield-side shield gap issubstantially less than the trailing shield-write pole gap.

Other features and benefits that characterize embodiments of thedisclosure will be apparent upon reading the following detaileddescription and review of the associated drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates an embodiment of a data storage device in whichembodiments of the present application can be used.

FIG. 1B is a schematic illustration of a head including one or moretransducer elements above a magnetic recording medium.

FIG. 2A depicts a bearing surface view of a perpendicular magneticrecording (PMR) transducer in accordance with one embodiment.

FIG. 2B depicts a side view of the PMR transducer of FIG. 2A.

FIG. 3A is a graph illustrating a time dependence of erasure fields,compared to a write pole field and a trailing shield field.

FIG. 3B is a bearing surface view of a portion of a write head in whicha magnetization distribution at the bearing surface is illustrated.

FIG. 4A is a graph showing an efficiency of magnetization reversal underStoner-Wolfarth conditions.

FIG. 4B is a graph showing a calculated relative efficiency of anerasure field applied for a predetermined total duration with a fastrise-time and decay.

FIGS. 5A, 5B, 5C and 6 are bearing surface views of write heads inaccordance with different embodiments.

FIG. 7 is a graph illustrating an impact of trailing shield-side shieldgap on relative erasure.

FIG. 8 is a flow diagram of a method embodiment.

FIGS. 9A-9G illustrate process steps for fabricating a write head of thetype shown in FIG. 5A.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Embodiments of the disclosure relate to a write head with a reduced sideto trailing shield spacing compared to a spacing between a write poleand the trailing shield to reduce erasure. However, prior to providingdetails regarding the different embodiments, a description of anillustrative operating environment is provided below.

FIG. 1A shows an illustrative operating environment in which certainrecording head embodiments as disclosed herein may be incorporated. Theoperating environment shown in FIG. 1A is for illustration purposesonly. Embodiments of the present disclosure are not limited to anyparticular operating environment such as the operating environment shownin FIG. 1A. Embodiments of the present disclosure are illustrativelypracticed within any number of different types of operatingenvironments.

It should be noted that like reference numerals are used in differentfigures for same or similar elements. It should also be understood thatthe terminology used herein is for the purpose of describingembodiments, and the terminology is not intended to be limiting. Unlessindicated otherwise, ordinal numbers (e.g., first, second, third, etc.)are used to distinguish or identify different elements or steps in agroup of elements or steps, and do not supply a serial or numericallimitation on the elements or steps of the embodiments thereof. Forexample, “first,” “second,” and “third” elements or steps need notnecessarily appear in that order, and the embodiments thereof need notnecessarily be limited to three elements or steps. It should also beunderstood that, unless indicated otherwise, any labels such as “left,”“right,” “front,” “back,” “top,” “bottom,” “forward,” “reverse,”“clockwise,” “counter clockwise,” “up,” “down,” or other similar termssuch as “upper,” “lower,” “aft,” “fore,” “vertical,” “horizontal,”“proximal,” “distal,” “intermediate” and the like are used forconvenience and are not intended to imply, for example, any particularfixed location, orientation, or direction. Instead, such labels are usedto reflect, for example, relative location, orientation, or directions.It should also be understood that the singular forms of “a,” “an,” and“the” include plural references unless the context clearly dictatesotherwise.

FIG. 1A is a schematic illustration of a data storage device 100including a data storage medium and a head for reading data from and/orwriting data to the data storage medium. As shown in FIG. 1A, the datastorage device 100 includes a data storage medium or disc 102 and a head104. The head 104 including one or more transducer elements (not shownin FIG. 1A) is positioned above the data storage medium 102 to read datafrom and/or write data to the data storage medium 102. In the embodimentshown, the data storage medium 102 is a rotatable disc or other magneticstorage medium that includes a magnetic storage layer or layers. Forread and write operations, a spindle motor 106 (illustratedschematically) rotates the medium 102 as illustrated by arrow 107 and anactuator mechanism 110 positions the head 104 relative to data tracks onthe rotating medium 102. Both the spindle motor 106 and actuatormechanism 110 are connected to and operated through drive circuitry 112(schematically shown). The head 104 is coupled to the actuator mechanism110 through a suspension assembly which includes a load beam 120connected to an actuator arm 122 of the mechanism 110 for examplethrough a swage connection.

The one or more transducer elements of the head 104 are coupled to headcircuitry 132 through flex circuit 134 to encode and/or decode data.Although FIG. 1A illustrates a single load beam 120 coupled to theactuator mechanism 110, additional load beams 120 and heads 104 can becoupled to the actuator mechanism 110 to read data from or write data tomultiple discs of a disc stack. The actuator mechanism 110 isrotationally coupled to a frame or deck (not shown) through a bearing124 to rotate about axis 126. Rotation of the actuator mechanism 110moves the head 104 in a cross track direction as illustrated by arrow130.

FIG. 1B is a detailed illustration (side view) of the head 104 above themedium 102. The one or more transducer elements on the head 104 arefabricated on a slider 140 to form a transducer portion 142 of the head104. The transducer portion 142 shown includes write elementsencapsulated in an insulating structure to form a write assembly 144 ofthe head. As shown, the head 104 includes a bearing surface (forexample, an air bearing surface (ABS)) 146 along a bottom surface 150 ofthe head or slider facing the medium 102. The head 104 is coupled to theload beam 120 through a gimbal spring 151 coupled to a top surface 152of the head or slider 140 facing away from the medium 102. The medium102 can be a continuous storage medium, a discrete track medium, a bitpatterned medium or other magnetic storage medium including one or moremagnetic recording layers.

During operation, rotation of the medium or disc 102 creates an air flowin direction 107 as shown in FIG. 1B along the air bearing surface 146of the slider 140 from a leading edge 154 to the trailing edge 156 ofthe slider 140 or head 104. Air flow along the air bearing surface 146creates a pressure profile to support the head 104 and slider 140 abovethe medium 102 for read and/or write operations. As shown, thetransducer portion 142 is formed at or near the trailing edge 156 of theslider 140. A transducer/head portion in accordance with one embodimentis described below in connection with FIGS. 2A and 2B.

FIGS. 2A and 2B depict ABS and side views, respectively, of aperpendicular magnetic recording (PMR) transducer 200. The PMRtransducer 200 may be a part of a merged head including the writetransducer 200 and a read transducer (not shown). Alternatively, themagnetic recording head may be a write head only including the writetransducer 200. The PMR transducer elements shown in FIGS. 2A and 2B areillustratively included in a recording head such as recording head 104of FIGS. 1A and 1B.

The write transducer 200 includes an under-layer/substrate 202, a mainpole 204, a trailing shield 206 and side shields 208. The under-layer202 may include multiple structures which are under the pole 204. Thewrite transducer 200 may also include other components including but notlimited to coils (denoted by reference numeral 210 in FIG. 2B) forenergizing the main pole 204.

The main pole 204 resides over under-layer 202 and includes sidewalls212 and 214. Sidewalls 212 and 214 are separated from the side shields208 by non-magnetic side shield gaps (SSGs) 216. The top (trailing)surface of the main pole 204 may have a beveled portion 218. The bottom(leading) surface of the main pole 204 may also include a leadingsurface bevel 220. At the bearing surface, the leading surface of themain pole 204 has a leading edge 205 and a trailing edge 207, which areconnected by side edges of sidewalls 212 and 214. A trailing shield gap(TSG) 222 is formed between the trailing shield 206 and the main pole204. In write head/transducer 200, the TSG 222 extends over or outsidethe SSGs 216 in a cross-track direction, forming overhangs 224 thatseparate the trailing shield 206 from portions of the side shields 208.The overhangs 224 may be produced by a write head fabrication processthat employs photo patterning to define a shape and dimensions of TSG222 as part of the steps for its formation. In general, a recording headwith a TSG including overhangs of the type shown in FIG. 2A may havecertain on-track performance advantages, but may also produce side trackerasure (STE) and adjacent track interference (ATI) which may bedetrimental to a reliability of the recording head, particularly at highdata-writing rates.

FIG. 3A is a graph 300 illustrating a time dependence of erasure fields,compared to a write field and a trailing shield field, and FIG. 3Billustrates locations of those fields at the bearing surface. In FIG.3A, horizontal axis (x axis) 302 represents time in picoseconds (ps) andvertical axis (y axis) 304 represents magnetic field in Tesla. Plot 306illustrates a variation of the write field (located at 307 between thewrite pole and the trailing shield in FIG. 3B) over time. Similarly,plot 308 illustrates a variation of the trailing shield field (locateddirectly under the trailing shield at 309 in FIG. 3B) over time. Also,plot 310 illustrates a variation of the erasure field (located at thepoint of erasure 311 in FIG. 3B) over time. As can be seen in FIG. 3A,point 312 is a peak erasure field that occurs substantially at a time ofreversal of the write pole field.

As has been confirmed by numerous iterations of modeling and experiment,a proximal STE (where proximal indicates 1-3 tracks away from the trackon which the write operation with the write head takes place) isdominated by a very fast, about 50 ps of total duration, impulse oferasure fields created between the corner of the side shield and thetrailing shield (311 in FIG. 3B). This occurs while the write pole tipundergoes reversal and does not participate in flux creation. Theerasure field then has two components: perpendicular to the ABS, createdby the charges on the side shield's surface, and a downtrack component,created by the interaction with the trailing shield. The impact of thetwo components on erasure is very different. The perpendicular componentsubstantially immediately lowers the energy barrier, and thereforeduring its application there is an increased probability of thermalerasure. However, the magnetization response to the perpendicularcomponent is slow, and by itself does not lower the barrier any further.The downtrack component however applies significant torque and perturbsthe magnetization. Its impact on erasure is determined substantially byhow far away a media magnetization moves from an equilibrium conditionas a result of such perturbation.

In the case of a very long duration of the applied field, the erasure isdominated by the events occurring during the time when the field isapplied. The impact of both components combined is very roughlyproportional to the effective or Stoner-Wolfarth field, which to thezeroth order accuracy can be simply inserted into the Arrhenius formulato estimate the reduction of energy barrier and the resulting erasure.

Of course, when the duration of field application approaches zero, sodoes the erasure impact (e.g., probability of magnetization reversal inthe media). However, in a limit of very short (sub 100 ps), but non-zeroduration, the impact is driven by a combination of factors substantiallydifferent from the extreme cases of either zero or very long duration.First, in this case, the magnetization returns to the unperturbeddirection during the timeframe comparable with the duration of erasurefield application. This means that, if the initial perturbation issignificant, it substantially impacts the erasure probability. Second,the probability of erasure during the application of the erasure fieldpurely due to the energy barrier reduction caused by the perpendicularcomponent of the field remains relatively small.

The estimation of magnetization dynamics in the media and therefore themaximum deviation from the equilibrium depends on a multitude offactors, including such that are difficult to evaluate directly (e.g.,effective damping). However, the impact on the effectiveness of theerasure field is typically such that, for the same amplitude, the highangle components gain ever more than for the case of Stoner-Wolfarthproblem (illustrated in FIGS. 4A and 4B), although the exact magnitudeof the gain remains debatable.

FIG. 4A is a graph 400 showing an efficiency of magnetization reversalunder Stoner-Wolfarth conditions (long duration, large applied field,large effective damping). In FIG. 4A, horizontal axis (x axis) 402represents angle in degrees and vertical axis 404 represents effectivewriting. FIG. 4B is a graph 450 showing a calculated relative efficiencyof erasure (Arrhenius process assumed) field applied for 50 ps of totalduration with fast rise-time and decay. In FIG. 4B, horizontal axis 452represents angle in degrees and vertical axis 454 represents effectiveerasure.

Since the location of erasure is relatively well established (top cornerof the side shield and the gap above it), changing the writer design atthis location can directly impact the erasure field for the purpose of(1) reducing the absolute amplitude of the erasure field, and (2)reducing the angle of the erasure field, thereby causing a substantialreduction of the downtrack component of the erasure field.

Embodiments of the disclosure reduce both the amplitude and the angle ofthe erasure field and thus the probability of erasure (seen in FIGS. 4Aand 4B) generated in the side shield corner by reducing the gap betweenthe front and side shields in the overhang regions (e.g., 224 of FIG. 2)of the write head. Examples of such embodiments are shown in FIGS. 5A,5B, 5C and 6 and described below.

FIG. 5A is a bearing surface view of a write head 500 in accordance witha first embodiment. Write head 500 of FIG. 5A includes a TSG 522 withoverhang regions 524 that are similar to overhang regions 224 of writehead 200 of FIG. 2A. However, as can be seen in FIG. 5A, overhangregions 524 have a reduced (non-zero) thickness 526 compared to athickness 528 of a remaining portion of TSG 522 that is between writepole 204 and trailing shield 206. In FIG. 5A, the reduction in thicknessof the overhang regions 524 is accomplished by extending portions of thetrailing shield 206 towards the side shields 208.

In some embodiments, overhang regions 524 include a single layer ofmaterial denoted by reference numeral 530. In some embodiments, theportion of TSG 522 between the write pole 204 and the trailing shield206 may include multiple layers. In some embodiments, the multiplelayers may include layer 530 and one or more additional layers (e.g.,532, 534, etc.). In general, any suitable number of layers (one or more)may be employed to form regions 524 and/or the portion of TSG 522between the write pole 204 and the trailing shield 206. In theembodiment shown in FIG. 5A, trailing edge 207 of the write pole 204 andupper surfaces 538 of the side shields 208 may be substantially flush.Also, portions of the trailing shield 206 over the side shields 208 areat a lower level than the portion of the trailing shield 206 that isabove the write pole 204.

FIG. 5B is a bearing surface view of a write head 550 in accordance witha second embodiment. The embodiment of FIG. 5B is similar to write head500 of FIG. 5A. However, to reduce the thickness of overhang regions524, instead of extending portions of the trailing shield 206 towardsthe side shields 208, the side shields 208 are extended towards thetrailing shields. Although not shown in FIG. 5B, in write head 550, anysuitable number of layers (one or more) may be employed to form regions524 and/or the portion of TSG 522 between the write pole 204 and thetrailing shield 206. In the embodiment shown in FIG. 5B, the trailingedge 207 of the write pole 204 is at a lower level than the uppersurfaces 538 of the side shields 208.

FIG. 5C is a bearing surface view of a write head 575 in accordance witha third embodiment. The embodiment of FIG. 5C is similar to write heads500 and 550 of FIGS. 5A and 5B, respectively. However, to reduce thethickness of overhang regions 524, both the trailing shield 206 and theside shields 208 are extended towards each other in write head 575 ofFIG. 5C. Although not shown in FIG. 5C, in write head 575, any suitablenumber of layers (one or more) may be employed to form regions 524and/or the portion of TSG 522 between the write pole 204 and thetrailing shield 206. In the embodiment shown in FIG. 5C, the trailingedge 207 of the write pole 204 is at a lower level than the uppersurfaces 538 of the side shields 208. Also, portions of the trailingshield 206 over the side shields 208 are at a lower level than theportion of the trailing shield 206 that is above the write pole 204.

FIG. 6 is a bearing surface view of a write head 600 in accordance witha fourth embodiment. In the embodiment of FIG. 6, the reduction inthickness of the overhang regions 524 is accomplished by extendingportions of the trailing shield 206 towards the side shields 208.However, in write head 600, the portions of the trailing shield 206 overregions 524 are at a lower level than the trailing edge 207 of the writepole 204 (e.g., lower surfaces 601 of trailing shield 206 are belowtrailing edge 207). Also, in the embodiment of FIG. 6, top surfaces 538of the side shields 208 are closer to the leading edge 205 than in thewrite head embodiments of FIGS. 5A, 5B and 5C. Although not shown inFIG. 6, in write head 600, any suitable number of layers (one or more)may be employed to form regions 524 and/or the portion of TSG 522between the write pole 204 and the trailing shield 206.

An erasure event in the side shield cannot close flux through the writepole, and typically excites opposite charges in the trailing shield.Bringing the trailing shield closer to the side shield in accordancewith the above-described embodiments both diminishes the perpendicularcomponent of the erasure field (as the opposite charges in the trailingshield create a perpendicular component of the opposite sign), andconfines the downtrack component to the area roughly proportional to thegap thickness. If the gap thickness is compared to the distance betweenthe writer and media surfaces, the erasure impact is reducedconsiderably. This is illustrated in FIG. 7, which is a modeled exampleof an impact of a gap between the trailing shield and the side shields.In the example shown in FIG. 7, a nominal TSG is 25 nanometers (nm). Inthe graph shown in FIG. 7, a horizontal axis 700 represents a gapbetween the trailing shield and the side shields in nm, and a verticalaxis 702 represents relative (e.g., nominal) erasure.

It should be noted that the write head 550 configuration shown in FIG.5B may increase the amount of shield material directly on top of theerasure spot, which may somewhat increase the perpendicular component ofthe erasure field. However, in write head 550, the undershoot in thetrailing shield is also driven further towards the center tracklocation, resulting in improved performance.

Referring back to FIGS. 5A, 5B and 5C, certain additions/alterations maybe made to write heads such as 500, 550 and 575 to further reduceerasure fields. For example, in some embodiments, a side shield caplayer having a low saturation magnetization may be provided in each sideshield 208. In write heads 500, 550 and 575, write side shield caplayers are shown with dashed lines and denoted by reference numeral208B. In such embodiments, each side shield 208 includes a main sideshield layer 208A and the side shield cap layer 208B. The side shieldcap layers 208B are adjacent to the overhang portions 524. Thesaturation magnetization value of the side shield cap layers 208B isless than a saturation magnetization value of the main side shieldlayers 208A. Though erasure fields in the media are reduced by thereduction in spacing between the trailing shield 206 and the sideshields 208 in the overhang regions 524, the magnetization alignment inthe shields 208 is still strongly concentrated around the corner of theside shield 208 and the trailing shield 206, and any reduction inmagnetization at that corner (e.g., by the inclusion of low saturationmagnetization layer 208B) is likely to reduce the erasure fieldsfurther. Another example involves providing a notch in the trailingshield. Extending the trailing shield 206 into the overhang regions 524by way of the notch allows for limited reduction of the write field witha smaller gap, compared to a non-notch design. Yet another exampleinvolves making the overhang regions 524 substantially wider than theoverhang regions 224 shown in FIG. 2A. Compared to the wider gap,increase in the width of the overhang 524 may result in substantiallyweaker increase of erasure, while comparable improvement in the dynamicgradient is provided.

FIGS. 8 and 9A-9F illustrate steps carried out during manufacturing of awrite head such as 500 of FIG. 5A. FIG. 8 is a flow diagram 800 of anexample method of forming the write head such as 500 FIG. 5A. Theprocess sequence intercepts the write head build at a stage where thetop bevel has been formed (218 in FIG. 2B) as shown in FIG. 9A. FIG. 9Aillustrates bearing surface view of a first partial write head structureor substrate 900 that includes side shields 902, side shield gap layers904 and write pole 906. Process step 802 of FIG. 8 indicates that such apartial write head structure is provided.

Starting with first partial write head structure 900, step 804 of FIG. 8is carried out. Step 804 involves depositing a multi-layered trailingshield gap 908 over the substrate 900 to provide a second partial writehead structure 910. The multi-layered trailing shield gap 908 has afirst thickness 912. In one embodiment, the multi-layered structure mayinclude a first thin metal layer 914, an insulation layer 916, anactivated carbon layer 918 that is recessed behind a bearing surface ofthe write head and shown in FIG. 9D, and a second thin metal layer 920.In a particular embodiment, the first thin metal layer 914 and thesecond thin metal layer 920 may be non-magnetic layers including, forexample, at least one of Ru, Cr, NiRu, NiCr, Ta or alloys thereof. Itshould be that other non-magnetic metals may also be used to form layers914 and 920. Each of layers 914 and 920 may be between about 1 nm andabout 10 nm thick. In some embodiments, the insulation layer 916includes alumina (Al₂O₃). The second thin metal layer 920 protects theinsulation layer 916 from some of the subsequent processes. Insulationlayer 916 may have a thickness in the range of 5-25 nm.

On second partial write head structure 910, in accordance with step 806of FIG. 8, a masking material 922 (see FIG. 9C) is deposited over afirst portion of the multi-layered trailing shield gap 908 directlyabove write pole 906 such that second portions of the multi-layeredtrailing shield gap 908 above the side shields 902 are unprotected bythe masking material 922. This step may involve utilizing photopatterning to define a dimension of the first portion of the trailingshield gap 908. The third partial write head structure that includes themasking material (e.g., photoresist) 922 shown in FIG. 9C is denoted byreference numeral 924.

In accordance with step 808 of FIG. 8, a material removal process iscarried out to remove material from the trailing shield gap 908 that isunprotected by the masking material to provide the second portions witha reduced second thickness relative to the first thickness 912. Thematerial removal process may involve several sub steps. Examples of suchsub steps are provided below.

In one embodiment, the second metal layer 920 previously deposited isremoved by an etch or a mill process, which is denoted by referencenumeral 926 in FIG. 9C. Process 926 exposes the activated carbon layer918 that is recessed behind the bearing surface. The fourth partialwrite head structure with the exposed activated carbon layer 918 isdenoted by reference numeral 928 and shown in FIG. 9D.

On the fourth partial write head structure 928, a material removalprocess 930 such as an inductively coupled plasma (ICP) etch process iscarried out as shown in FIG. 9D to remove the exposed activated carbonlayer 918. A wet etch process or an ICP process or a reactive ion-beam(RIB) etch process may then be performed to remove portions of theinsulation layer 916 that are not covered by the masking material (e.g.,the photoresist) 922 and the remaining portion of the second metal layer920. In one embodiment, a deliberately selected chemistry (e.g.,Tetramethylammonium hydroxide (TMAH)) that has a relatively low etchingrate may be utilized to provide sufficient control and less undercuttingof the insulation layer 916. The previously deposited first thin metallayer 914 serves as a wet etch stop layer or an ICP or a RIB stop layer,and therefore is left behind after the wet etch is completed. Theresulting fifth partial write head structure 932 is shown in FIG. 9E.

The masking material 922 is removed from the fifth partial write headstructure 932, and a magnetic layer 934 (shown in FIG. 9F) is depositedover the wafer including the remaining portion of structure 932.Magnetic layer 934 may have a thickness between about 30 nm and 100 nm.Dimensions of magnetic layer 934 and metal layer 914 are definedtogether. A masking material 936 of the defined dimension is includedover the magnetic layer 934. The resulting sixth intermediate partialwrite head structure is denoted by reference numeral 938 in FIG. 9F.

Portions of the magnetic layer 934 and the metal layer 914, which arenot covered by the masking material 936, are then removed by, forexample, an ion mill or etch process. The material removal processresults in layer 914 having portions that extend outside layer 916/920,thereby providing a reduced gap between layer 934 and side shield 902.Masking material 936 is then removed to provide a seventh partial writehead structure 940 shown in FIG. 9G. Other steps are then carried out tocomplete the formation of the write head.

The illustrations of the embodiments described herein are intended toprovide a general understanding of the structure of the variousembodiments. The illustrations are not intended to serve as a completedescription of all of the elements and features of apparatus and systemsthat utilize the structures or methods described herein. Many otherembodiments may be apparent to those of skill in the art upon reviewingthe disclosure. Other embodiments may be utilized and derived from thedisclosure, such that structural and logical substitutions and changesmay be made without departing from the scope of the disclosure.Additionally, the illustrations are merely representational and may notbe drawn to scale. Certain proportions within the illustrations may beexaggerated, while other proportions may be reduced. Accordingly, thedisclosure and the figures are to be regarded as illustrative ratherthan restrictive.

One or more embodiments of the disclosure may be referred to herein,individually and/or collectively, by the term “invention” merely forconvenience and without intending to limit the scope of this applicationto any particular invention or inventive concept. Moreover, althoughspecific embodiments have been illustrated and described herein, itshould be appreciated that any subsequent arrangement designed toachieve the same or similar purpose may be substituted for the specificembodiments shown. This disclosure is intended to cover any and allsubsequent adaptations or variations of various embodiments.Combinations of the above embodiments, and other embodiments notspecifically described herein, will be apparent to those of skill in theart upon reviewing the description.

The Abstract of the Disclosure is provided to comply with 37 C.F.R. §1.72(b) and is submitted with the understanding that it will not be usedto interpret or limit the scope or meaning of the claims. In addition,in the foregoing Detailed Description, various features may be groupedtogether or described in a single embodiment for the purpose ofstreamlining the disclosure. This disclosure is not to be interpreted asreflecting an intention that the claimed embodiments require morefeatures than are expressly recited in each claim. Rather, as thefollowing claims reflect, inventive subject matter may be directed toless than all of the features of any of the disclosed embodiments.

The above-disclosed subject matter is to be considered illustrative, andnot restrictive, and the appended claims are intended to cover all suchmodifications, enhancements, and other embodiments, which fall withinthe true spirit and scope of the present disclosure. Thus, to themaximum extent allowed by law, the scope of the present disclosure is tobe determined by the broadest permissible interpretation of thefollowing claims and their equivalents, and shall not be restricted orlimited by the foregoing detailed description.

What is claimed is:
 1. A method of forming a write head, the methodcomprising: providing a substrate having a write pole and side shieldsfor the write pole, the substrate having an upper surface including atrailing edge of the write pole and upper surfaces of the side shields;depositing a multi-layered trailing shield gap over the substrate, themulti-layered trailing shield gap having a first thickness andcomprising a first thin metal layer, an insulation layer, an activatedcarbon layer that is recessed behind a bearing surface of the write headand a second thin metal layer; depositing a masking material over afirst portion of the multi-layered trailing shield gap directly abovethe write pole such that second portions of the multi-layered trailingshield gap above the side shields are unprotected by the maskingmaterial; removing a material from the multi-layered trailing shield gapunprotected by the masking material to provide the second portions witha reduced second thickness relative to the first thickness of the firstportion; removing the masking material; and forming a trailing shieldover the first portion of the multi-layered trailing shield gap havingthe first thickness and over the second portion of the multi-layeredtrailing shield gap having the second thickness.
 2. The method of claim1 and wherein removing material from the multi-layered trailing shieldgap unprotected by the masking material comprises removing unprotectedportions of the second thin metal layer, the insulation layer and theactivated carbon layer to leave behind the first thin metal layer thatprovides the second thickness of the second portion of the multi-layeredtrailing shield gap.
 3. The method of claim 1 and wherein the first thinmetal layer and the second thin metal layer are non-magnetic layerscomprising at least one of Ru, Cr, NiRu, NiCr, Ta or alloys thereof, andwherein the insulation layer comprises alumina.
 4. A method of forming awrite head, the method comprising: providing a substrate having a writepole and side shields for the write pole, the substrate having an uppersurface including a trailing edge of the write pole and upper surfacesof the side shields; depositing a multi-layered trailing shield gap overthe substrate with one of the multiple layers of the multi-layeredtrailing shield gap being an activated carbon layer, the multi-layeredtrailing shield gap having a first thickness; depositing a maskingmaterial over a first portion of the multi-layered trailing shield gapdirectly above the write pole such that second portions of themulti-layered trailing shield gap above the side shields are unprotectedby the masking material; removing a material from the multi-layeredtrailing shield gap unprotected by the masking material to provide thesecond portions with a reduced second thickness relative to the firstthickness of the first portion; removing the masking material; andforming a trailing shield over the first portion of the multi-layeredtrailing shield gap having the first thickness and over the secondportion of the multi-layered trailing shield gap having the secondthickness.
 5. The method of claim 4 and wherein the multi-layeredtrailing shield gap comprises: a first thin metal layer; an insulationlayer; and a second thin metal layer.
 6. The method of claim 5 andwherein removing material from the multi-layered trailing shield gapunprotected by the masking material comprises removing unprotectedportions of the second thin metal layer, the insulation layer and theactivated carbon layer to leave behind the first thin metal layer thatprovides the second thickness of the second portion of the multi-layeredtrailing shield gap.
 7. The method of claim 6 and wherein the first thinmetal layer and the second thin metal layer are non-magnetic layerscomprising at least one of Ru, Cr, NiRu, NiCr, Ta or alloys thereof, andwherein the insulation layer comprises alumina.
 8. A method of forming awrite head, the method comprising: providing a substrate having a writepole and side shields for the write pole, the substrate having an uppersurface including a trailing edge of the write pole and upper surfacesof the side shields; depositing a multi-layered trailing shield gap overthe substrate, the multi-layered trailing shield gap having a firstthickness and comprising a first thin metal layer, an insulation layerand a second thin metal layer; depositing a masking material over afirst portion of the multi-layered trailing shield gap directly abovethe write pole such that second portions of the multi-layered trailingshield gap above the side shields are unprotected by the maskingmaterial; removing a material from the multi-layered trailing shield gapunprotected by the masking material to provide the second portions witha reduced second thickness relative to the first thickness of the firstportion; removing the masking material; and forming a trailing shieldover the first portion of the multi-layered trailing shield gap havingthe first thickness and over the second portion of the multi-layeredtrailing shield gap having the second thickness.
 9. The method of claim8 and wherein removing material from the multi-layered trailing shieldgap unprotected by the masking material comprises removing unprotectedportions of the second thin metal layer and the insulation layer toleave behind the first thin metal layer that provides the secondthickness of the second portion of the multi-layered trailing shieldgap.
 10. The method of claim 8 and wherein the first thin metal layerand the second thin metal layer are non-magnetic layers comprising atleast one of Ru, Cr, NiRu, NiCr, Ta or alloys thereof, and wherein theinsulation layer comprises alumina.
 11. The method of claim 8 andwherein the multi-layered trailing shield gap comprises: an activatedcarbon layer that is recessed behind a bearing surface of the writehead.
 12. The method of claim 8 and wherein removing material from themulti-layered trailing shield gap unprotected by the masking materialcomprises removing unprotected portions of the first thin metal layer,the insulation layer and the activated carbon layer.